JP7365576B2 - Decorative sheet, display device with decorative sheet, and method for manufacturing the decorative sheet - Google Patents

Description

The present invention relates to a decorative sheet, a display device with a decorative sheet having the decorative sheet, and a method for manufacturing the decorative sheet.

For example, as described in Patent Document 1, a decorative sheet that is illuminated with light from the back side is known. This decorative sheet displays a pattern provided on a layer forming its surface when it is not illuminated with light from the back side. On the other hand, it is said that the decorative sheet may have minute openings formed therein so that light can pass therethrough. The light projected onto the back surface of the decorative sheet is transmitted through the decorative sheet at the position where the opening is formed. Therefore, when the decorative sheet is illuminated with light in a predetermined pattern, the decorative sheet can display the predetermined pattern.

According to such a decorative sheet, display can be performed by illuminating the decorative sheet from the back side, while a specific pattern can be displayed when no display is performed. Therefore, when the display is not illuminated from the back, the pattern of the decorative sheet allows the decorative sheet to be in harmony with the surroundings. This also makes it possible to give an excellent public display value to a device that performs some sort of display.

Japanese Patent Application Publication No. 2000-132126

By the way, the opening of the decorative sheet can be formed by melting and removing a part of the sheet-like material that forms the decorative sheet using a laser beam. However, since the openings are so minute that they cannot be visually recognized, it is difficult to form the openings in a highly precise arrangement by irradiating only a portion of the decorative sheet with laser light. For this reason, in conventional decorative sheets, in many cases, the entire area is formed with an opening as a transmission region. In other words, with conventional decorative sheets, it has not been possible to improve the design expression when illuminated from the back by changing the arrangement pattern of the openings. It has been difficult to express designs that correspond with high precision when illuminated from the back.

The present invention has been made in consideration of the above points, and an object of the present invention is to improve the design of a decorative sheet that is illuminated from the back.

The first decorative sheet according to the present invention is
A decorative sheet arranged facing a surface light source device,
a base design layer,
a pattern layer provided on a portion of the base design layer,
An opening is provided that penetrates the base design layer and reaches the pattern layer,
The infrared absorption rate of the pattern layer is higher than the infrared absorption rate of the base design layer.

In the first decorative sheet according to the present invention, the absorption spectrum of the patterned layer may have a peak in the infrared region.

The second decorative sheet according to the present invention is
A decorative sheet arranged facing a surface light source device,
a base design layer,
a pattern layer provided on a portion of the base design layer,
An opening is provided that penetrates the base design layer and reaches the pattern layer,
The absorption spectrum of the patterned layer has a peak in the infrared region.

In the first or second decorative sheet according to the present invention, the absorption spectrum of the patterned layer may have a peak at a wavelength of 900 nm or more and 1300 nm or less.

In the first or second decorative sheet according to the present invention, the peak of the absorption spectrum of the patterned layer in the infrared region may be 3% or more.

In the first or second decorative sheet according to the present invention, the peak of the absorption spectrum in the infrared region of the pattern layer may be higher than the peak of the absorption spectrum in the infrared region of the base design layer. .

The third decorative sheet according to the present invention is
A decorative sheet arranged facing a surface light source device,
a base design layer,
a pattern layer provided on a portion of the base design layer,
An opening is provided that penetrates the base design layer and reaches the pattern layer,
The peak of the absorption spectrum of the patterned layer in the infrared region is higher than the peak of the absorption spectrum of the base design layer in the infrared region.

In the first to third decorative sheets according to the present invention, the visible light transmittance in the region where the pattern layer is provided is higher than the visible light transmittance in the region where the pattern layer is not provided. You can also do this.

The fourth decorative sheet according to the present invention is
A decorative sheet arranged facing a surface light source device,
a base design layer,
a pattern layer provided on a portion of the base design layer,
The visible light transmittance in the region where the pattern layer is provided is higher than the visible light transmittance in the region where the pattern layer is not provided,
The infrared absorption rate of the pattern layer is higher than the infrared absorption rate of the base design layer.

The fifth decorative sheet according to the present invention is
A decorative sheet arranged facing a surface light source device,
a base design layer,
a pattern layer provided on a portion of the base design layer,
The visible light transmittance in the region where the pattern layer is provided is higher than the visible light transmittance in the region where the pattern layer is not provided,
The absorption spectrum of the patterned layer has a peak in the infrared region.

The sixth decorative sheet according to the present invention is
A decorative sheet arranged facing a surface light source device,
a base design layer,
a pattern layer provided on a portion of the base design layer,
The visible light transmittance in the region where the pattern layer is provided is higher than the visible light transmittance in the region where the pattern layer is not provided,
The peak of the absorption spectrum of the patterned layer in the infrared region is higher than the peak of the absorption spectrum of the base design layer in the infrared region.

In the first to sixth decorative sheets according to the present invention, the aperture ratio in the region where the pattern layer is provided may be higher than the aperture ratio in the region where the pattern layer is not provided. .

In the first to sixth decorative sheets according to the present invention, the pattern layer may be colored.

In the first to sixth decorative sheets according to the present invention, the pattern layer may be colorless and transparent.

In the first to sixth decorative sheets according to the present invention, a recessed portion may be provided in a region of the base design layer where the pattern layer is not provided.

In the first to sixth decorative sheets according to the present invention, the base design layer may contain an inorganic material.

In the first to sixth decorative sheets according to the present invention, the inorganic material may be in the form of flakes.

In the first to sixth decorative sheets according to the present invention, the maximum length of the inorganic material may be 5 μm or more.

In the first to sixth decorative sheets according to the present invention, the pattern layer may include particles, and the maximum length of the particles may be smaller than the maximum length of the flaky inorganic material.

In the first to sixth decorative sheets according to the present invention, the inorganic material may contain any one of aluminum, titanium oxide, and mica.

In the first to sixth decorative sheets according to the present invention, the visible light reflectance of the base design layer may be 5% or more.

In the first to sixth decorative sheets according to the present invention, the visible light absorption rate of the base design layer may be 3% or less.

The first to sixth decorative sheets according to the present invention are
further comprising a light shielding layer provided on the opposite side of the base design layer from the pattern layer,
The visible light transmittance of the light shielding layer may be lower than the visible light transmittance of the base design layer.

The display device with a decorative sheet according to the present invention includes:
A surface light source device,
A decorative sheet that is any one of the first to sixth decorative sheets according to the present invention described above and is arranged to face the surface light source device.

The method for manufacturing a decorative sheet according to the present invention includes:
A method for producing any one of the first to sixth decorative sheets according to the present invention described above,
producing a first film that will form the pattern layer and a second film that will form the base design layer;
The method includes a step of removing a portion of the first film and the second film by irradiating the second film with a laser beam from the side of the second film to form an opening.

In the method for manufacturing a decorative sheet according to the present invention, the absorption rate of the first film at the wavelength of the laser beam may be higher than the absorption rate of the second film at the wavelength of the laser beam.

In the method for manufacturing a decorative sheet according to the present invention, the absorption rate of the first film at the wavelength of the laser beam may be 3% or more.

In the method for manufacturing a decorative sheet according to the present invention, the wavelength of the laser beam may be 900 nm or more and 1300 nm or less.

According to the present invention, it is an object of the present invention to improve the design of a decorative sheet that is illuminated from the back.

FIG. 1 is a diagram for explaining one embodiment, and is an exploded perspective view schematically showing a display device with a decorative sheet. FIG. 2 is a cross-sectional view of the display device with a decorative sheet shown in FIG. FIG. 2A is a cross-sectional view of the base design layer of the decorative sheet. FIG. 2B is a cross-sectional view of the base design layer and pattern layer of the decorative sheet. FIG. 3 is a plan view showing the decorative sheet in a state where the surface light source device of the display device with the decorative sheet of FIG. 1 is turned off. FIG. 4 is an enlarged view of region Z in FIG. FIG. 5 is a sectional view taken along line VV in FIG. 4. FIG. 6 is a plan view showing the decorative sheet in a state where the surface light source device of the display device with the decorative sheet of FIG. 1 is turned on. FIG. 7 is a diagram for explaining an example of a method for manufacturing a decorative sheet. FIG. 8 is a diagram for explaining an example of a method for manufacturing a decorative sheet. FIG. 9 is a diagram for explaining an example of a method for manufacturing a decorative sheet. FIG. 10 is a diagram for explaining an example of a method for manufacturing a decorative sheet. FIG. 11 is a diagram for explaining an example of a method for manufacturing a decorative sheet. FIG. 12 is a diagram corresponding to FIG. 3, and is a diagram for explaining a modified example of the decorative sheet. FIG. 13 is a diagram corresponding to FIG. 4, and is an enlarged diagram of region Z in FIG. FIG. 14 is a diagram corresponding to FIG. 5, and is a diagram for explaining another modification of the decorative sheet. FIG. 15 is a diagram corresponding to FIG. 10, and is a diagram for explaining a reference example of a method for manufacturing a decorative sheet. FIG. 16 is a diagram corresponding to FIG. 11, and is a diagram for explaining a reference example of a method for manufacturing a decorative sheet.

Hereinafter, one embodiment of the present invention will be described with reference to the drawings. In addition, in the drawings attached to this specification, for convenience of illustration and ease of understanding, the scale and the vertical and horizontal dimensional ratios are appropriately changed and exaggerated from those of the actual drawings.

Note that, in this specification, the terms "layer", "sheet", and "film" are not distinguished from each other based only on the difference in designation. For example, the term "layer" is a concept that includes members that may be called sheets or films.

In addition, terms such as "parallel," "perpendicular," and "identical," and values of length and angle used in this specification that specify shapes, geometric conditions, and their degree, etc., are strictly The term shall be interpreted to include the extent to which similar functions can be expected, without being bound by meaning.

FIG. 1 is an exploded perspective view schematically showing a display device 1 with a decorative sheet according to an embodiment of the present invention. As shown in FIG. 1, the display device 1 with a decorative sheet includes a surface light source device 10 having a light emitting surface 11, and a decorative sheet 20 disposed facing the light emitting surface 11. In the display device 1 with a decorative sheet, the decorative sheet 20 is arranged so that the side on which a light shielding layer 24 described later is provided faces the surface light source device 10. In the illustrated example, the display device 1 with a decorative sheet is shown in a flat shape, but each component of the display device 1 with a decorative sheet is curved, so that the display device 1 with a decorative sheet 1 may have a curved shape.

The surface light source device 10 is a device that emits light in a planar manner. The surface light source device 10 is not particularly limited, and various types, such as an edge light type and a direct type device, can be used. The illustrated surface light source device 10 has a light emitting surface 11 on the front surface facing the decorative sheet 20. Further, of the front surface of the surface light source device 10 facing the decorative sheet 20, a region surrounding the light emitting surface 11 is a non-light emitting surface 12 configured by a frame (bezel). That is, the front surface of the surface light source device 10 facing the decorative sheet 20 includes a light emitting surface 11 and a non-light emitting surface 12 located around the light emitting surface 11.

The decorative sheet 20 is arranged to face the light emitting surface 11 of the surface light source device 10, and covers at least the entire light emitting surface 11 so that the light emitting surface 11 is not directly observed from the outside. The decorative sheet 20 has dimensions larger than the dimensions of the light emitting surface 11 so that it can cover the entire light emitting surface 11 of the surface light source device 10 . The illustrated decorative sheet 20 has a size that covers the entire front area of the surface light source device 10 including the light emitting surface 11 and the non-light emitting surface 12 located around the light emitting surface 11. That is, the decorative sheet 20 hides the entire surface light source device 10. In the example shown in FIG. 1, the decorative sheet 20 is a flat member that extends in the same direction as the light emitting surface 11 of the surface light source device 10 as a whole. The thickness of the decorative sheet 20 can be, for example, 20 μm or more and 550 μm or less.

The decorative sheet 20 displays a design and imparts design to the display device 1 with a decorative sheet. In this embodiment, the decorative sheet 20 includes a base design layer 22 and a pattern layer 23 provided on a portion of the base design layer 22. The base design layer 22 is formed as a so-called solid layer, and is formed as a layer that spreads two-dimensionally, or in other words, as a layer that spreads planarly. On the other hand, the pattern layer 23 is formed on a portion of the base design layer 22. For example, the pattern layer 23 is provided in a predetermined pattern on one surface of the base design layer 22.

As shown in FIGS. 2 and 3, the decorative sheet 20 includes a first area A1 and a second area A2. The illustrated decorative sheet 20 is plane-divided into a first area A1 and a second area A2. The pattern layer 23 is provided in the first area A1 and is not provided in the second area A2 outside the first area A1. In the illustrated example, the first area A1 is provided at the center of the decorative sheet 20, as shown in FIG. 3, and is an area forming a pattern of the alphabet "D".

Further, the illustrated decorative sheet 20 further includes a base film 21 and a light shielding layer 24 in addition to the base design layer 22 and pattern layer 23, as shown in FIG. In the decorative sheet 20 shown in FIG. 2, a pattern layer 23 is provided in a first region A1 on one surface of the base film 21. The base design layer 22 is formed to cover one surface of the base film 21 and the entire area of the pattern layer 23. That is, the illustrated base design layer 22 extends over the entire area of the base film 21. The light shielding layer 24 is laminated on the side of the base design layer 22 opposite to the pattern layer 23. The light shielding layer 24 extends over the entire area of the base design layer 22. Hereinafter, each component included in the decorative sheet 20 will be explained in order.

The base film 21 supports the base design layer 22, pattern layer 23, and light shielding layer 24 that are laminated on the base film 21. The base film 21 is a transparent film-like member. The base film 21 may be made of any material as long as it transmits visible light and can appropriately support the base design layer 22, pattern layer 23, and light shielding layer 24. For example, polymethyl methacrylate, polyethylene terephthalate, etc. , polyethylene naphthalate, polycarbonate, polystyrene, cyclic polyolefin, ABS (acrylonitrile butadiene styrene copolymer), and the like. Further, the base film 21 may have a thickness of 10 μm or more and 500 μm or less, considering visible light transmittance and appropriate support for the base design layer 22, pattern layer 23, and light shielding layer 24. preferable.

Transparent means the transmittance at each wavelength when measured using a spectrophotometer ("UV-3100PC" manufactured by Shimadzu Corporation, JIS K 0115 compliant product) within the measurement wavelength range of 380 nm to 780 nm. It means that the visible light transmittance specified as the average value of is 80% or more.

The base design layer 22 forms the design displayed by the decorative sheet 20 together with the pattern layer 23 . The base design layer 22 can form designs such as figures, patterns, designs, colors, pictures, photographs, characters, marks, letters, and numbers. Further, in this embodiment in which the pattern layer 23 is provided separately from the base design layer 22, the base design layer 22 can also express a design as a background of the pattern layer 23. For example, the base design layer 22 may display a wood grain pattern, a marble pattern, or a geometric pattern as a design that can harmonize with the surrounding environment in which the display device 1 with decorative sheet is provided. The design formed by the base design layer 22 may be represented by a single color or by a plurality of colors. In addition, the base design layer 22 has a color that does not harm the design of the pattern formed by the pattern layer 23 due to color mixture with the pattern layer 23 when observed by an external observer, making it easy to avoid color mixture, for example. Preferably, the color is white or silver.

The base design layer 22 can be a layer containing an inorganic material, as shown in FIG. 2A. The base design layer 22 shown in FIG. 2A includes a binder resin 22a and an inorganic material 22b dispersed in the binder resin 22a. The inorganic material contained in the base design layer 22 is not particularly limited, and may be aluminum, titanium oxide, or mica. The base design layer 22 containing these inorganic materials can be made white or silver, for example, so that changes in the color of the pattern layer 23 can be effectively suppressed. The inorganic material made of aluminum or mica can be a flaky material with a maximum length of 5 μm or more. According to such a large flake-like inorganic material, a positive design can be expressed by the base design layer 22.

Further, in order to display the design formed by the base design layer 22 brightly, the visible light reflectance of the base design layer 22 is preferably 5% or more, and more preferably 10% or more. Visible light reflectance was measured using an ultraviolet/visible/near-infrared spectrophotometer (Shimadzu UV-3600) and an integrating sphere accessory (ISR-3100) at an incident angle of 8° in the visible range from 380 nm to 780 nm. The reflectance (total reflectance) can be measured and the average reflectance can be specified.

Furthermore, from the viewpoint of making the design expression by the base design layer 22 more effective, the visible light absorption rate of the base design layer 22 may be 3% or less. When the visible light absorption rate of the base design layer 22 is 3% or less, the base design layer 22 can display white or a white color close to white, and the design formed by the base design layer 22 can be The design quality can be improved. The visible light absorption rate is the absorption rate at each wavelength when measured within the measurement wavelength range of 380 nm to 780 nm using, for example, an ultraviolet-visible near-infrared spectrophotometer (for example, "V-770" manufactured by JASCO Corporation) can be specified as the average value of

On the other hand, since the wavelength of visible light and the wavelength of infrared rays are close to each other, materials that have a low visible light absorption rate generally also have a low infrared absorption rate. When the visible light absorption rate of the base design layer 22 is low, the infrared absorption rate of the base design layer 22 is also low. Specifically, the infrared absorption rate of the base design layer 22 tends to be 3% or less.

As described above, the pattern layer 23 is provided only in the first area A1 of the decorative sheet 20. The pattern layer 23 is provided on a portion of the base design layer 22 to form a pattern. The shape of the first region A1 forming the pattern of the pattern layer 23 is not particularly limited and can be selected as appropriate. The pattern layer 23 may display figures, designs, colors, pictures, characters, marks, pictograms, letters, numbers, etc. by the pattern itself. Further, the pattern layer 23 may display pictures such as figures, designs, colors, pictures, characters, marks, pictograms, letters and numbers in the first area A1 where the pattern layer 23 is provided. good.

In one illustrated example, the pattern layer 23 is formed in an area shaped like the letter "D" located at the center of the decorative sheet 20, as shown in FIG. The illustrated pattern layer 23 is a monochromatic layer. In other words, this pattern layer 23 displays the alphabet "D" in a single color. On the other hand, the illustrated base design layer 22 is a monochromatic layer different from the pattern layer 23. That is, the base design layer 22 displays the background of the alphabet "D" in a color different from that of the pattern layer 23.

Furthermore, the pattern layer 23 has a property of absorbing infrared rays. As will be described later, in the manufacturing process of the decorative sheet 20, the first film 31 that forms the pattern layer 23 absorbs infrared rays that are not absorbed by the second film 32 that forms the base design layer 22. Absorbs laser light. Therefore, the pattern layer 23 absorbs infrared rays more easily than the base design layer 22. In other words, the infrared absorption rate of the pattern layer 23 is higher than the infrared absorption rate of the base design layer 22. Moreover, the infrared absorption rate herein means the average absorption rate of infrared rays having a wavelength of 900 nm or more and 1300 nm or less. Such a wavelength is the wavelength of laser light emitted from an infrared laser light source that is generally available at low cost and has sufficient output, and is suitable for the wavelength of laser light used in the manufacturing process of the decorative sheet 20. . In addition, the infrared absorption rate is the average value of the absorption rate at each wavelength when measured within the measurement wavelength range of 900 nm to 1300 nm using, for example, an ultraviolet-visible near-infrared spectrophotometer V-770 manufactured by JASCO Corporation. can be specified as.

The absorption spectrum of the patterned layer 23 has an absorption peak in the infrared region (wavelength range of 780 nm or more and 15,000 nm or less) so that the patterned layer 23 easily absorbs infrared rays. Specifically, the absorption spectrum of the patterned layer 23 preferably has an absorption peak at a wavelength of 780 nm or more and 15,000 nm or less, and preferably has an absorption peak at a wavelength of 800 nm or more and 10,000 nm or less. is more preferable, and even more preferably has an absorption peak at a wavelength of 900 nm or more and 1300 nm or less. Further, the peak of the absorption rate of the absorption spectrum of the patterned layer 23 is preferably 3% or more, more preferably 5% or more. Here, the absorption spectrum means the distribution of light absorption rate [%] at each wavelength [nm]. Further, in order for the patterned layer 23 to easily absorb infrared rays, it is preferable that the peak of the absorption spectrum of the patterned layer 23 in the infrared region is higher than the peak of the absorption spectrum of the base design layer 22 in the infrared region.

The base design layer 22 and the pattern layer 23 can be formed as layers containing a pigment or the like in a binder resin. Further, as described above, the base design layer 22 and the pattern layer 23 may be layers containing an inorganic material such as aluminum, titanium oxide, or mica in a binder resin.

Preferably, the thickness of the base design layer 22 and the thickness of the pattern layer 23 are greater than or equal to a thickness that allows sufficient design expression. On the other hand, it is preferable that the thickness of the base design layer 22 and the thickness of the pattern layer 23 be equal to or less than a thickness that enables removal by laser light, which will be described later. Specifically, the thickness of the base design layer 22 can be set to 1 μm or more and 40 μm or less. The thickness of the pattern layer 23 can be 1 μm or more and 20 μm or less. In the illustrated example, the thickness of the base design layer 22 in the second area A2 is the sum of the thickness of the base design layer 22 in the first area A1 and the thickness of the pattern layer 23 in the first area A1. It's sato.

The light shielding layer 24 is provided so as to cover the base design layer 22 from the side facing the surface light source device 10. The light shielding layer 24 has a visible light shielding property so that visible light from the surface light source device 10 does not enter the base design layer 22. Therefore, the visible light transmittance of the light shielding layer 24 is preferably lower than the visible light transmittance of the base design layer 22. The light-shielding layer 24 may contain light-absorbing particles in a binder resin, for example. Examples of light-absorbing particles include black pigments such as carbon black and titanium black. When the base design layer 22 is covered with a sufficiently thick light-shielding layer 24, the design formed by the base design layer 22 can be formed darkly and clearly. As a specific example, the thickness of the light shielding layer 24 can be set to 1 μm or more and 20 μm or less.

As mentioned above, visible light transmittance is measured using a spectrophotometer ("UV-3100PC" manufactured by Shimadzu Corporation, JIS K 0115 compliant product) within the measurement wavelength range of 380 nm to 780 nm. It can be specified as the average value of transmittance at each wavelength.

By the way, as shown in FIG. 2, the decorative sheet 20 penetrates the light shielding layer 24 and the base design layer 22 to reach the pattern layer 23 in the area where the pattern layer 23 is provided, that is, the first area A1. An opening H is formed. By forming such openings H, the decorative sheet 20 can promote light transmission in the first region A1. From the viewpoint of transmitting visible light, the depth DH of the opening H is preferably 90% or more of the thickness T1 excluding the base film 21 in the first area A1 of the decorative sheet 20, and typically In this case, the opening H penetrates the pattern layer 23 and reaches the base film 21 (see FIG. 5). That is, typically, an opening (through hole) H passing through the light shielding layer 24, the pattern layer 23, and the base design layer 22 is formed. This opening H functions as a transmitting portion 28 for the light emitted by the surface light source device 10 when illuminated from the back by the surface light source device 10. As shown in FIG. 5, in the illustrated example, the opening H in the first region A1 is formed as a through hole that penetrates the decorative sheet 20.

As shown in FIG. 4, the transparent part 28 consisting of the penetrating opening H is a part where the base design layer 22, pattern layer 23, and light shielding layer 24 are not formed when observing the decorative sheet 20 from the front. . In order to sufficiently transmit the light emitted by the surface light source device 10, the proportion of the area occupied by the penetrating openings H in the area of the first region A1 of the decorative sheet 20, that is, the aperture ratio is set to 10% or more. It is preferably 15% or more, and even more preferably 20% or more. On the other hand, in order to sufficiently ensure the visibility of the pattern layer 23 when the surface light source device 10 is turned off, the aperture ratio in the first region A1 is preferably 50% or less.

Note that FIG. 4 shows the area Z in FIG. 3 in an enlarged manner.

In this way, in the first region A1 of the decorative sheet 20, light transmission is promoted when the surface light source device 10 is turned on. On the other hand, in the second area A2 of the decorative sheet 20, transmission of light is restricted when the surface light source device 10 is turned on. Therefore, the aperture ratio, which is the ratio of the area occupied by the penetrating opening H, is larger in the first region A1 than in the second region A2. As a result, the visible light transmittance in the first region A1 where the pattern layer 23 is provided is higher than the visible light transmittance in the second region A2 where the pattern layer 23 is not provided. That is, the penetrating openings H are formed intensively in the first region A1 of the decorative sheet 20.

In the decorative sheet 20 shown in FIGS. 4 and 5, no opening H passing through the base design layer 22 is formed in a region where the pattern layer 23 is not provided, that is, in the second region A2. In the illustrated example, no through holes are provided in the second area A2 of the decorative sheet 20. Therefore, the aperture ratio in the illustrated second region A2 of the decorative sheet 20 is 0%, and the transmission of visible light in the second region A2 of the decorative sheet 20 is effectively regulated.

Note that, as shown in FIG. 5, a recess (opening that does not penetrate) R that does not penetrate the base design layer 22 may be formed in the second region A2 of the decorative sheet 20. As will be described later, this recess R is formed in the second region A2 when the opening H into the first region A1 is created. From the viewpoint of effectively blocking the transmission of light emitted by the surface light source device 10 when illuminated from the back by the surface light source device 10, the depth DR of the recessed portion R is set to the depth DR in the second region A2 of the decorative sheet 20. It is preferably 80% or less, and more preferably 70% or less, of the thickness T2 excluding the base film 21 at the position where the recess R is not formed. By forming the recess R in the second region A2 and adjusting its depth DR, the brightness of the second region A2 when the decorative sheet 20 is lit can be controlled. Thereby, the display contrast of the pattern layer 23 can be adjusted by adjusting the brightness balance between the first area A1 and the second area A2, thereby making it possible to express various designs.

In the example shown in FIG. 4, the plurality of openings H provided in the first region A1 are spaced apart from each other. Further, the plurality of openings H provided in the first region A1 are regularly arranged. By regularly arranging the openings H forming the transmission section 28, the light emitted by the surface light source device 10 can be transmitted through the first area A1 of the decorative sheet 20 with approximately uniform brightness. I can do it. Similarly, the plurality of recesses R provided in the second region A2 are spaced apart from each other. Further, the plurality of recesses R provided in the second region A2 are regularly arranged. By arranging the recesses R regularly, when the surface light source device 10 is turned on and emits visible light, the second area A2 of the decorative sheet 20 can be made to have uniform brightness.

Furthermore, in the decorative sheet 20, the openings H and the recesses R are arranged together and regularly. In the illustrated example, the plurality of openings H and the plurality of recesses R are arranged in a square arrangement, but they are not limited to this, and may be arranged in a honeycomb arrangement or a staggered arrangement, or, They may be arranged irregularly. The arrangement of the plurality of openings H and the arrangement of the plurality of recesses R may be different.

Furthermore, in the example shown in FIG. 4, the plurality of openings H provided in the first region A1 have the same shape in plan view. Specifically, each opening H has a circular shape in plan view. Since the plurality of openings H forming the transmission section 28 have a certain shape, the light emitted by the surface light source device 10 is transmitted through the first area A1 of the decorative sheet 20 with approximately uniform brightness. be able to. Similarly, in the example shown in FIG. 4, the plurality of recesses R provided in the second region A2 have the same shape in plan view. Specifically, each recess R has a circular shape in plan view. Since the recess R has a certain shape, the second area A2 of the decorative sheet 20 can have uniform brightness when the surface light source device 10 is turned on and emits visible light.

Furthermore, in the example shown in FIG. 4, the opening H and the recess R have the same shape in plan view. However, the present invention is not limited to the illustrated example, and the shapes of the openings H in plan view may be different among the plurality of openings H. Furthermore, the shapes of the recesses R in plan view may be different among the plurality of recesses R. Furthermore, the shape of the opening H in plan view may be different from the shape of the recess R in plan view.

In addition, from the viewpoint of the design of the decorative sheet 20, it is preferable that the individual openings H are not visually recognized. Similarly, it is preferable that the individual recesses R are also not visually recognized. From this point of view, the arrangement pitch PH of the plurality of openings H can be set to 60 μm or more and 160 μm or less. The maximum width WH of each opening H can be 30 μm or more and 130 μm or less. The area of each opening H can be set to 900 μm ² or more and 16900 μm ² or less. Further, the arrangement pitch PR of the plurality of recesses R can be set to 60 μm or more and 160 μm or less. The maximum width WR of each recess R can be 30 μm or more and 130 μm or less. The area of each recess R can be 900 μm ² or more and 16900 μm ² or less.

Next, the operation of the display device 1 with a decorative sheet according to the present embodiment will be explained.

When the surface light source device 10 is turned off and no visible light is emitted from the light emitting surface 11, as shown in FIG. , the pattern of the first area A1 in which the pattern layer 23 is formed is visible. That is, the pattern of the pattern layer 23 becomes visible. Further, the surface light source device 10 can be hidden by the decorative sheet 20. Furthermore, the design of the base design layer 22 itself makes it possible to harmonize the decoration sheet 20 with the surrounding environment in which the display device 1 with a decorative sheet is installed.

On the other hand, when the surface light source device 10 is turned on and visible light is emitted from the light emitting surface 11, the visible light transmittance of the first region A1 in which the opening H is formed is the same as the visible light transmittance of the second region A2. higher than the rate. As a result, the pattern in the first area A1 where the pattern layer 23 is formed can be seen to be brighter than when the surface light source device 10 is turned off, as shown in FIG. On the other hand, since the opening H is not formed in the second area A2, the visible light emitted by the surface light source device 10 has a high transmittance and cannot pass through the decorative sheet 20 in the second area A2. do not have. For this reason, the base design layer 22 is only visible by reflection of ambient light, and therefore is not observed as brightly as the pattern layer 23. That is, the pattern layer 23 can be clearly viewed with high contrast.

Note that the base design layer 22 is covered with a light shielding layer 24 from the surface light source device 10 side. Therefore, the light shielding layer 24 can effectively restrict visible light emitted by the surface light source device 10 from entering the base design layer 22. Therefore, in the first region A1, visible light passes through the base design layer 22 and the pattern layer 23, and the pattern layer 23 is visually recognized in an unintended color due to the color mixture of the base design layer 22 and the pattern layer 23. can be effectively avoided. Furthermore, in the illustrated example, the boundary B between the light-emitting surface 11 and the non-light-emitting surface 12 of the surface light source device 10 is located within the second area A2 of the decorative sheet 20, but visible light does not pass through the second area A2. Since it is not actively transmitted, this boundary B can be made invisible.

Next, an example of a method for manufacturing the decorative sheet 20 will be described.

First, as shown in FIG. 8, the first film 31 on which the pattern layer 23 will be formed is formed in the first region A1 of the base film 21. Next, as shown in FIG. 9, a second film 32 that will form the base design layer 22 is formed so as to cover the base film 21 and the first film 31. Thereafter, as shown in FIG. 10, a third film 33 that will form the light shielding layer 24 is formed to cover the second film 32. The first film 31, the second film 32, and the third film 33 can be formed by applying and drying a resin composition containing an inorganic material, a pigment, etc. that will be included in each corresponding layer. Note that the resin composition can be applied using a known coating technique. At this time, applying the resin composition constituting the first film 31 only to the first area A1 on the base film 21 can be performed extremely easily, quickly, and accurately using known techniques.

In the laminate 34 formed in this manner, it is preferable that the first film 31 has a higher infrared absorption rate than the second film 32. It is preferable that the peak of the absorption spectrum of the first film 31 is higher than the peak of the absorption spectrum of the second film 32. The absorption spectrum of the first film 31 preferably has a peak in the infrared region. The absorption spectrum of the first film 31 may have a peak at a wavelength of 900 nm or more and 1300 nm or less. The peak of the absorption spectrum of the first film 31 in the infrared region may be 3% or more.

Next, as shown in FIG. 11, a laser beam Lx is irradiated from the laser device 40 to the position where the opening H is to be formed. The laser light is irradiated from the side opposite to the base film 21 side, that is, from the side of the second film 32 and the third film 33. The wavelength of the laser beam Lx is in the infrared region from 780 nm to 1300 nm, for example from 900 nm to 1300 nm. As a specific example of the laser beam Lx, a laser beam of an Nd:YAG laser having a wavelength of 1064 nm can be used. By using the infrared laser beam Lx emitted from the laser device 40, the influence of the color and pattern of the base design layer 22 and pattern layer 23 is weakened, and the laser beam Lx on the second film 32 forming the base design layer 22 is reduced. It is easier to set the absorption rate of the laser beam Lx in the first film 31 forming the pattern layer 23 higher than the absorption rate of the pattern layer 23 .

In the example shown in FIG. 11, the laser beam Lx is irradiated onto the laminate 34 from the third film 33 side while shifting the emission part of the laser device 40 at a constant pitch. At this time, the irradiation area of the laser beam Lx on the third film 33 of the laminate 34 is almost the entire area of the third film 33 or the clearly visible area of the third film 33 without any complicated control. The laser beam Lx may be irradiated to a region other than the peripheral region outside the first region A1. That is, the irradiation area of the laser beam Lx, which has an extremely fine spot diameter due to the formation of a fine opening, is not controlled with high precision, but is controlled to be limited to, for example, only the first area A1. The laser beam Lx is irradiated from the laser device 40 by controlling only the pitch and output of the laser device 40. Since the first film 31 indicating the first area A1 is hidden by the third film 33, it is assumed that positioning control to irradiate only the first area A1 with the laser beam Lx will be complicated. Productivity can be greatly improved by omitting complicated tasks.

Note that the output of the laser beam Lx emitted from the laser device 40 is set to a level that does not completely melt and remove the second film 32 in the second region A2. That is, the output of the laser device 40 is suppressed to prevent an opening penetrating the third film 33 and the second film 32 from being formed in the second region A2. In the example shown in FIG. 11, the third film 33 and the second film 32 are removed to about half the total thickness of the third film 33 and the second film 32 in the second region A2. As a result, a recess R is formed that penetrates the third film 33 and extends halfway through the second film 32.

On the other hand, in the first region A1, at the position irradiated with the laser beam Lx, the third film 33, the second film 32, and the first film 31 are all removed, and a penetrating opening 29 leading to the base film 21 is removed. is formed. In the first region A1, the first film 31 disposed at the farthest position from the incident side of the laser beam Lx absorbs the laser beam Lx in the wavelength range projected from the laser device 40 with a high absorption rate (for example, 3% or more). More preferably, it can be absorbed at an absorption rate of 5% or more. Therefore, even when the laser beam Lx is irradiated with such an output that the second film 32 on the first film 31 cannot be completely removed, as shown in FIG. The first film 31 is melted by reaching the film 31 and being efficiently absorbed by the first film 31. Along with this, the second film 32 adjacent to the melted first film 31 is also melted. Furthermore, as the melted first film 31 evaporates, the melted second film 32 also evaporates.

As described above, by irradiating the laser beam Lx, a recess R is formed in the second region A2 of the laminate 34, and an opening H is formed in the first region A1 of the laminate 34, in which the first film 31 is provided. I can do that. In this manufacturing method, the irradiation conditions of the laser beam Lx when irradiating the first area A1 and the irradiation conditions of the laser beam Lx when irradiating the second area A2 can be made the same. Therefore, there is no need to specify the first area A1 of the laminate 34. Note that since the laser beam Lx is irradiated from the side of the third film 33 that can hide the first film 31, the first area A1 where the first film 31 is provided is specified and the laser beam is applied only to the first area A1. Irradiating Lx is complicated. In this regard, in the manufacturing method described above, the identification of the first area A1 is omitted and the entire area of the third film 33 is irradiated with the laser beam Lx under constant irradiation conditions, thereby selectively affecting the first area A1. An opening H can be formed, and a recess R can be selectively formed in the second region A2. Therefore, manufacturing of the decorative sheet 20 with excellent design can be greatly simplified.

The third film 33, second film 32, and first film 31 that were not irradiated with the laser beam Lx and were not removed come to form the light shielding layer 24, the base design layer 22, and the pattern layer 23, respectively. The decorative sheet 20 is manufactured through the above steps.

By the way, as shown in FIG. 15, the decorative sheet 120 that does not include the pattern layer 23 is obtained by laminating the second film 132 and the third film 133 on the base film 121, and outputting it to the position where the transparent part 128 is to be formed. It can be manufactured by irradiating the laser beam Ly with adjusted. When the decorative sheet 120 is manufactured in this way, as shown in FIG. A residue 132r of the second film 132 may remain. There may be a difference in design between the transparent portion 128 in which such a residue 132r remains and the transparent portion 128 in which no residue 132r remains. Specifically, the design may be displayed darker than the design that should be displayed due to the residue 132r. Due to this difference in design, a pattern of shading occurs in the design displayed by the decorative sheet 120, and the design that should be displayed by the decorative sheet 120 is impaired. may worsen.

As a result of intensive studies by the inventors of the present invention, it has been found that such a residue 132r is caused by the second film 132 not sufficiently absorbing the laser beam Ly. Specifically, due to the fact that the second film 132 does not sufficiently absorb the laser beam Ly, the second film 132 is not sufficiently melted and evaporated, and a portion of the second film 132 remains and the transmitting portion 128 It remains in The second film 132 that absorbs the laser beam Ly and the second film 132 that does not sufficiently absorb the laser beam Ly are, for example, the colors at each position of the base design layer 122 that are formed by the second film 132 at each position. It was also confirmed that this could occur due to differences in the pattern and pattern.

On the other hand, in the decorative sheet 20 of the present embodiment, a pattern layer 23 that absorbs infrared rays is arranged between the base film 21 and the base design layer 22 in the first region A1 where the opening H is to be formed. There is. That is, in the manufacturing process of the decorative sheet 20, the first film 31 that forms the pattern layer 23 is placed between the base film 21 and the second film 32. The infrared absorption rate of the pattern layer 23 is higher than the infrared absorption rate of the base design layer 22. That is, in the manufacturing process of the decorative sheet 20, the infrared absorption rate of the first film 31 is higher than the infrared absorption rate of the second film 32. Therefore, even if the second film 32 does not sufficiently absorb the laser light forming the opening H, the first film 31 can sufficiently absorb the laser light. By melting and evaporating the first film 31 that has absorbed the laser beam, the second film 32 and third film 33 stacked on the first film 31 can be removed without leaving almost any residue. That is, in the first region A1 of the decorative sheet 20, it is possible to prevent residue from remaining in the opening H.

Further, the absorption spectrum of the patterned layer 23 has an absorption peak in the infrared region. That is, in the manufacturing process of the decorative sheet 20, the absorption spectrum of the first film 31 has an absorption peak in the infrared region. Therefore, the first film 31 can efficiently absorb infrared rays of the peak wavelength. When the peak wavelength of the first film 31 is close to the wavelength of the laser light Lx forming the opening H, the laser light is efficiently absorbed in the first film 31. By melting and evaporating the first film 31 that has absorbed the laser beam, the second film 32 and third film 33 stacked on the first film 31 are removed with almost no residue left behind, thereby forming a decorative sheet. It is possible to make it difficult for residue to remain inside the opening H formed in the first region A1 of 20.

Furthermore, the peak of the absorption spectrum of the patterned layer 23 in the infrared region is higher than the peak of the absorption spectrum of the base design layer 22 in the infrared region. That is, in the manufacturing process of the decorative sheet 20, the peak of the absorption spectrum of the first film 31 in the infrared region is higher than the peak of the absorption spectrum of the second film 32 in the infrared region. Therefore, the first film 31 can absorb infrared rays more efficiently than the second film 32. In other words, the first film 31 can absorb laser light more efficiently than the second film 32. By melting and evaporating the first film 31 that has absorbed the laser beam, the second film 32 and third film 33 stacked on the first film 31 are removed with almost no residue left behind, thereby forming a decorative sheet. It is possible to make it difficult for residues to remain attached to the inside of the opening H formed in the first region A1 of 20.

The absorption spectrum of the patterned layer 23 has an absorption peak at a wavelength of 900 nm or more and 1300 nm or less. That is, in the manufacturing process of the decorative sheet 20, the absorption spectrum of the first film 31 has an absorption peak at a wavelength of 900 nm or more and 1300 nm or less. Therefore, the first film 31 can efficiently absorb infrared rays of this wavelength. When the laser beam Lx forming the opening H has a wavelength of 900 nm or more and 1300 nm or less, the first film 31 absorbs the laser beam Lx more efficiently. By melting and evaporating the first film 31 that has absorbed the laser beam Lx, the second film 32 and third film 33 stacked on the first film 31 are removed without leaving almost any residue, and the decoration is completed. It is possible to prevent residue from remaining in the opening H formed in the first region A1 of the sheet 20.

Moreover, the peak of the absorption rate of the absorption spectrum of the patterned layer 23 is 3% or more. That is, in the manufacturing process of the decorative sheet 20, the peak of the absorption rate of the absorption spectrum of the first film 31 is 3% or more. Therefore, infrared rays at the peak of the absorption rate of the absorption spectrum of the first film 31 can be absorbed more efficiently. When the laser light forming the opening H has a wavelength that is at or near the peak of the first film 31, the laser light is absorbed more efficiently in the first film 31. By melting and evaporating the first film 31 that has absorbed the laser beam, the second film 32 and third film 33 stacked on the first film 31 are removed with almost no residue left behind, thereby forming a decorative sheet. It is possible to make it difficult for residues to remain in the opening H formed in the first region A1 of 20.

Furthermore, the base design layer 22 contains an inorganic material such as titanium oxide. If the inorganic material does not sufficiently absorb the laser light in the second film 32, it tends to remain as a residue in the opening H. However, if the pattern layer 23 that absorbs infrared rays is disposed between the base film 21 and the base design layer 22 as in the present embodiment, the pattern layer 23 is removed in the manufacturing process of the decorative sheet 20. Since the first film 31 that comes to be formed sufficiently absorbs infrared rays, even if the second film 32 contains such an inorganic material, the first film 31 that has absorbed the laser beam Lx will not melt and evaporate. In this way, the second film 32 can be removed without leaving almost any residue. That is, it is possible to prevent residue from remaining in the opening H formed in the first region A1 of the decorative sheet 20.

In particular, the inorganic material includes aluminum, titanium oxide, or mica. When such a material is included, the visible light reflectance of the base design layer 22 can be 5% or more. Such a base design layer 22 tends to be difficult to absorb infrared rays, and is difficult to be removed even when irradiated with laser light. For this reason, it has been difficult to form the opening H by irradiating the second film 32 with laser light. On the other hand, if the pattern layer 23 that absorbs infrared rays is arranged between the base film 21 and the base design layer 22 as in this embodiment, the pattern layer 23 is Since the first film 31 that comes to be formed sufficiently absorbs infrared rays Lx, even if the second film 32 hardly absorbs infrared rays, the first film 31 that has absorbed the laser beam melts and evaporates, leaving no residue. The second film 32 can be removed with almost no residue left behind. That is, it is possible to prevent residue from remaining in the opening H formed in the first region A1 of the decorative sheet 20.

In the embodiment described above, the method for manufacturing a decorative sheet includes a first film 31 that forms a pattern layer 23 on a base film 21 and a first film that forms a base design layer 22 on a base film 21. a step of stacking two films 32; a step of removing a portion of the first film 31 and the second film 32 by irradiating laser light from the second film 32 side to form an opening H; Contains. According to such a method of manufacturing a decorative sheet, the laser beam Lx for forming the opening H is not sufficiently absorbed in the second film 32 that forms the base design layer 22, and on the other hand, The laser beam Lx can be sufficiently absorbed in the first film 31 forming the pattern layer 23. Therefore, in the first region A1 where the first film 31 is provided, the first film 31 that has absorbed the laser beam Lx is melted and evaporated, thereby removing the second film 32 stacked on the first film 31. Thus, an opening H through which visible light can sufficiently pass can be formed. On the other hand, in the second region A2 where the first film 31 is not provided, the laser beam Lx is not easily absorbed by the second film 32, so that a shallow recess R with a depth DR can be formed. That is, even if the entire area of the second film 32 is irradiated with the laser beam Lx, only the first region A1 where the first film 31 forming the pattern layer 23 is provided has an opening through which visible light can sufficiently pass. A portion H may be formed. That is, according to the present embodiment, by adjusting the formation area of the first film 31, it is possible to control the formation area of the opening H that can sufficiently transmit visible light. Adjusting the formation area of the first film 31 is much easier than adjusting the irradiation area of the laser beam Lx. Therefore, the decorative sheet 20 having an excellent design can be easily and inexpensively produced.

In one specific example of the embodiment described above, the absorption rate of the first film 31 at the wavelength of the laser beam Lx is higher than the absorption rate of the second film 32 at the wavelength of the laser beam Lx. According to this example, the second film 32 stacked on the first film 31 can be stably removed by melting and evaporating the first film 31 that has absorbed the laser beam Lx. Therefore, the opening H that can sufficiently promote the transmission of visible light can be stably formed in the first region A1. On the other hand, in the second region A2 where the first film 31 is not provided, a shallow recess R can be formed in place of the opening H that can sufficiently promote transmission of visible light. In other words, the formation region of the opening H can be controlled with high precision by the pattern of the first film 31.

In one specific example of the embodiment described above, the absorption rate of the first film 31 at the wavelength of the laser beam Lx used for forming the opening H is set to be 3% or more. According to such an example, the first film 31 forming the pattern layer 23 can sufficiently absorb the laser beam Lx. Therefore, in the first region A1 where the pattern layer 23 is provided, the first film 31 that has absorbed the laser beam Lx is melted and evaporated, thereby stably maintaining the second film 32 laminated on the first film 31. The opening H that can sufficiently promote the transmission of visible light can be stably formed in the first region A1. In other words, the formation region of the opening H can be controlled with high precision by the pattern of the first film 31.

In the embodiment described above, the decorative sheet 20 disposed facing the surface light source device 10 includes a base design layer 22, a pattern layer 23 provided on a portion of the base design layer 22, have. In the first region A1 where the pattern layer 23 is provided, an opening H that penetrates the base design layer 22 and reaches the pattern layer 23 is provided. The visible light transmittance in the first region A1 where the pattern layer 23 is provided is higher than the visible light transmittance in the first region A1 where the pattern layer 23 is not provided. Here, the infrared absorption rate of the pattern layer 23 is higher than the infrared absorption rate of the base design layer 22, the absorption spectrum of the pattern layer 23 has a peak in the infrared region, or the pattern layer 23 has a peak in the infrared region. The peak of the absorption spectrum in the infrared region is higher than the peak of the absorption spectrum of the base design layer 22 in the infrared region. In such a decorative sheet 20, the openings H formed by laser light irradiation can transmit visible light with higher transmittance in the first area A1 where the pattern layer 23 is provided. . In other words, the opening H formed in the first area A1 where the pattern layer 23 is provided by irradiation with the laser beam Lx is formed in the second area A2 where the pattern layer 23 is not provided by irradiation with the laser beam Lx. This can contribute to improving the visible light transmittance of the decorative sheet 20 compared to the recessed portions R. Therefore, when the decorative sheet 20 is illuminated from the back side, the first area A1 where the pattern layer 23 is provided can be displayed brighter than the second area A2 where the pattern layer 23 is not provided. Therefore, the combination of the pattern layer 23 and the base design layer 22 can effectively improve the design and provide a display with excellent design.

In one specific example of the embodiment described above, the aperture ratio in the first area A1 where the pattern layer 23 is provided is higher than the aperture ratio in the second area A2 where the pattern layer 23 is not provided. There is. Thereby, the visible light transmittance in the first region A1 where the pattern layer 23 is provided can be stably made higher than the transmittance in the second region A2 where the pattern layer 23 is not provided.

In one specific example of the embodiment described above, the pattern layer 23 is a colored layer. According to this example, when the decorative sheet 20 is not illuminated from the back side, the pattern can be displayed by the color of the pattern layer 23. Furthermore, by illuminating the decorative sheet 20 from the back side, the pattern displayed by the pattern layer 23 can be displayed brightly using visible light. This makes it possible to vary the pattern display and improve the design.

In a specific example of the embodiment described above, a recess R is formed in the second region A2 of the base design layer 22 where the pattern layer 23 is not provided, from the side opposite to the side where the pattern layer 23 is provided. is provided. The depth DR of the recess R is 80% or less of the thickness of the decorative sheet 20 excluding the base film 21 at a position in the second region A2 where the recess R is not provided. According to this example, part of the visible light irradiated from the back surface can pass through the second region A2 of the decorative sheet 20 in the portion where the recess R as the bottomed hole is formed. That is, the brightness of the second region A2 where the pattern layer 23 is not provided can be adjusted by the depth DR of the recess R that does not penetrate through the surface. This makes it possible to further improve the design.

In one specific example of the embodiment described above, the base design layer 22 includes an inorganic material. According to this example, since the base design layer 22 contains an inorganic material, a richer design can be expressed. On the other hand, in the base design layer 22 containing an inorganic material, it becomes difficult to stably form a penetrating opening H by laser light irradiation. Therefore, this embodiment, in which the pattern layer 23 can be provided to stabilize the hole shape, is suitable for the decorative sheet 20 having the base design layer 22 containing an inorganic material.

In one specific example of the embodiment described above, the inorganic material includes titanium oxide. By using titanium oxide as an inorganic material, the design of the decorative sheet 20 can be significantly improved in combination with the pattern layer. On the other hand, the visible light absorption rate of the base design layer 22 containing titanium oxide decreases to about 3% or less, and the infrared absorption rate of the base design layer 22 containing titanium oxide also decreases to about 3% or less. It will drop. As a result, it becomes difficult to stably form an opening H through the base design layer 22 by irradiation with laser light. Therefore, this embodiment, in which the pattern layer 23 can be provided to stabilize the hole shape, is suitable for the decorative sheet 20 having the base design layer 22 containing titanium oxide as an inorganic material.

In one specific example of the embodiment described above, the visible light reflectance of the base design layer 22 is 5% or more. While the base design layer 22 with high reflectance allows rich design expression, it is difficult to stably form penetrating openings H in such a base design layer 22. Therefore, this embodiment, in which the pattern layer 23 can be provided to stabilize the hole shape, is suitable for the decorative sheet 20 having the base design layer 22 containing an inorganic material.

Although one embodiment has been described based on a specific example, the above-mentioned specific example is not intended to limit the one embodiment. The embodiment described above can be implemented in various other specific examples, and various omissions, substitutions, changes, and additions can be made without departing from the gist thereof.

Hereinafter, an example of the modification will be described with reference to the drawings. In the following explanation and the drawings used in the following explanation, the same reference numerals as those used for corresponding parts in the above specific example are used for parts that may be configured in the same way as in the above specific example, and redundant explanations are used. omitted.

In the specific example described above, the pattern layer 23 is a colored layer, but the pattern layer 23 is not limited to this example, and the pattern layer 23 may be a colorless and transparent layer. For example, the visible light transmittance of the patterned layer 23 can be set to 80% or more, and further to 85% or more. According to this example, when the surface light source device 10 is turned off and does not emit visible light, the pattern layer 23 is not visible, as shown in FIGS. 12 and 13. Therefore, the first area A1 and the second area A2 of the decorative sheet 20 cannot be separated, and only the base design layer 22 is visible. Here, FIG. 13 is a diagram corresponding to FIG. 4, and shows the region Z in FIG. 12 in an enlarged manner. On the other hand, when the surface light source device 10 is turned on and emits visible light, the pattern of the pattern layer 23 can be displayed brightly and clearly, as shown in FIG. According to such an example, the decorative sheet 20 can display a pattern that has not been visually recognized until then by being illuminated from the back side. That is, unexpected display can be performed, thereby improving the design.

Further, in the specific example described above, the decorative sheet 20 includes only one base design layer 22, but the present invention is not limited to this. As shown in FIG. 14, the decorative sheet 20 may include one or more additional base design layers in addition to the base design layer 22. Further base design layers may be constructed similarly to base design layer 22 described above. The further base design layer may be spread over the entire area of the decorative sheet 20 as a solid layer like the base design layer 22.

In the example shown in FIG. 14, the decorative sheet 20 has a second base design layer 22B provided on the opposite side of the base design layer 22 from the base film 21. In the example shown in FIG. 14, the base design layer 22 includes figures, patterns, designs, colors, pictures, photographs, characters, marks, pictures such as letters and numbers, especially woodgrain or marble-like pictures, and geometric patterns. It is formed as a pattern layer that displays . The second base design layer 22B is formed as a layer containing an inorganic material or a metallic layer containing a metal to make the pattern of the base design layer 22 stand out. By providing the second base design layer 22B, the design of the base design layer 22 can be enhanced. Such a decorative sheet 20 includes a fourth film that forms the second base design layer 22B, a second film 32 that forms the base design layer 22, and a light shielding layer 33. It can be produced by preparing a laminate 34 between the third film 33 and irradiating this laminate 34 with laser light.

Also in the decorative sheet 20 having the further base design layer 22B, the infrared absorption rate of the patterned layer 23 is higher than the infrared absorption rate of the base design layer 22 adjacent to the patterned layer, or the patterned layer 23 Since the peak of the absorption spectrum in the infrared region is higher than the peak of the absorption spectrum in the infrared region of the base design layer 22 adjacent to the pattern layer, the above-mentioned effects can be achieved. That is, according to such a decorative sheet 20, the openings H formed by laser light irradiation can transmit visible light with higher transmittance in the first region A1 where the pattern layer 23 is provided. It becomes like this. In other words, the opening H formed in the first area A1 where the pattern layer 23 is provided by irradiation with the laser beam Lx is formed in the second area A2 where the pattern layer 23 is not provided by irradiation with the laser beam Lx. This can contribute to improving the visible light transmittance of the decorative sheet 20 compared to the recessed portions R. Therefore, when the decorative sheet 20 is illuminated from the back side, the first area A1 where the pattern layer 23 is provided can be displayed brighter than the second area A2 where the pattern layer 23 is not provided. The combination of the pattern layer 23 and the base design layer 22 can effectively improve the design and provide a display with excellent design.

Furthermore, in the decorative sheet 20 having the further base design layer 22B, the infrared absorption rate of the pattern layer 23 is higher than the infrared absorption rate of the further base design layer (second base design layer 22B). Alternatively, the peak of the absorption spectrum in the infrared region of the patterned layer 23 is higher than the peak of the absorption spectrum in the infrared region of the further base design layer (second base design layer 22B), so that the above-mentioned The effects can be more pronounced.

Furthermore, in the above-described specific example, the inorganic material included in the base design layer 22 may be in the form of flakes. Since the flaky inorganic material has a high reflectance, the base design layer 22 can express a design with high gloss. Examples of flaky inorganic materials include aluminum and mica. The maximum length of the flaky inorganic material may be 5 μm or more. From the viewpoint of displaying a glittering design, the maximum length of the inorganic material is preferably 20 μm or more, for example. Further, from the viewpoint of circulation resistance, the maximum length of the inorganic material is preferably 60 μm or less, for example.

In this modification, as shown in FIG. 2B, the pattern layer 23 is formed as a layer containing particles 23b in a binder resin 23a, and the maximum length of the particles 23b included in the pattern layer 23 is longer than that of the base design layer 23. The length may be smaller than the maximum length of the flaky inorganic material 22b contained in the binder resin 22a. In particular, the maximum length of the particles contained in the pattern layer 23 is preferably one-half or less, more preferably one-fifth or less, of the maximum length of the inorganic material contained in the base design layer 22. preferable. Specifically, the maximum length of particles included in the pattern layer 23 may be 5 μm or less. The base design layer 22 containing a flake-like inorganic material with a long maximum length does not easily evaporate because heat is not transmitted to the entire binder resin even when irradiated with laser light. On the other hand, the pattern layer 23 in which particles with a short maximum length are used can easily transmit heat to the entire binder resin and evaporate easily, and can form an opening H by involving the base design layer 22 during evaporation. As a result, the opening H can be selectively formed in the area where the pattern layer 23 is formed, and the design created by the pattern layer 23 can be made to correspond to the design displayed through the opening H when illuminated from the back side. . Examples of materials for the particles included in the pattern layer 22 include processed cyanine products, phthalocyanine compounds, dithiol metal complexes, lanthanum hexaboride, cesium-doped tungsten oxide, naphthoquinone compounds, and diimonium compounds.

The maximum length of the flaky inorganic pigment included in the base design layer 22 and the particles included in the pattern layer 23 can be determined by, for example, measuring a cross section in the thickness direction of each layer using a scanning electron microscope (Hitachi S-4500). It can be calculated as the average value of the maximum length of 100 inorganic pigments or particles by observing at an acceleration voltage of 15 kV and observation magnification of 20,000 times. When exposing the cross section of each layer for observation, it may be cut with a microtome, or it may be rapidly frozen in liquid nitrogen and then cut with a diamond knife or an ion beam.

Further, in the specific example described above, the surface light source device 10 had the light emitting surface 11 in a rectangular shape, but the invention is not limited to this example. You can do it. In addition, the display device 1 with a decorative sheet further includes a patterned light-shielding film, and the patterned light-shielding film blocks a part of the light emitted from the light emitting surface 11 of the surface light source device 10, so that the decorative sheet 20 can be fixed in a predetermined manner. The pattern may be illuminated.

1 Display device with decorative sheet 10 Surface light source device 11 Light-emitting surface 12 Non-light-emitting surface 20 Decorative sheet 21 Base film 22 Base design layer 23 Pattern layer 24 Light-shielding layer 28 Transmissive portion 31 First film 32 Second film 33 Third Film 34 Laminate 40 Laser device A1 First area A2 Second area H Opening R Recess Lx Laser light

Claims (24)

A decorative sheet arranged facing a surface light source device,
a base design layer,
a pattern layer provided on a portion of the base design layer,
An opening is provided that penetrates the base design layer and reaches the pattern layer,
The decorative sheet has an infrared absorption rate of the pattern layer that is higher than an infrared absorption rate of the base design layer. The decorative sheet according to claim 1, wherein the absorption spectrum of the patterned layer has a peak in an infrared region. The decorative sheet according to claim 1 or 2 , wherein the absorption spectrum of the patterned layer has a peak at a wavelength of 900 nm or more and 1300 nm or less. The decorative sheet according to any one of claims 1 to 3 , wherein the pattern layer has an absorption peak of 3% or more in the absorption spectrum in the infrared region. The decorative sheet according to any one of claims 1 to 4 , wherein the peak of the absorption spectrum of the pattern layer in the infrared region is higher than the peak of the absorption spectrum of the base design layer in the infrared region. A decorative sheet arranged facing a surface light source device,
a base design layer,
a pattern layer provided on a portion of the base design layer,
An opening is provided that penetrates the base design layer and reaches the pattern layer,
The decorative sheet has an absorption spectrum peak in the infrared region of the pattern layer that is higher than an absorption spectrum peak in the infrared region of the base design layer. The decoration according to any one of claims 1 to 6 , wherein the visible light transmittance in the region where the pattern layer is provided is higher than the visible light transmittance in the region where the pattern layer is not provided. sheet. The decorative sheet according to any one of claims 1 to 7 , wherein the aperture ratio in the region where the pattern layer is provided is higher than the aperture ratio in the region where the pattern layer is not provided. The decorative sheet according to any one of claims 1 to 8 , wherein the pattern layer is colored. The decorative sheet according to any one of claims 1 to 8 , wherein the pattern layer is colorless and transparent. The decorative sheet according to any one of claims 1 to 10 , wherein a recessed portion is provided in a region of the base design layer where the pattern layer is not provided. The decorative sheet according to any one of claims 1 to 11 , wherein the base design layer contains an inorganic material. The decorative sheet according to claim 12 , wherein the inorganic material is in the form of flakes. The decorative sheet according to claim 13 , wherein the maximum length of the flaky inorganic material is 5 μm or more. The decorative sheet according to claim 13 or 14, wherein the pattern layer includes particles, and the maximum length of the particles is smaller than the maximum length of the flaky inorganic material. The decorative sheet according to any one of claims 12 to 15 , wherein the inorganic material contains any one of aluminum, titanium oxide, and mica. The decorative sheet according to any one of claims 1 to 16 , wherein the base design layer has a visible light reflectance of 5% or more. The decorative sheet according to any one of claims 1 to 17 , wherein the base design layer has a visible light absorption rate of 3% or less. further comprising a light shielding layer provided on the opposite side of the base design layer from the pattern layer,
The decorative sheet according to any one of claims 1 to 18 , wherein the visible light transmittance of the light shielding layer is lower than the visible light transmittance of the base design layer. A surface light source device,
A display device with a decorative sheet, comprising: the decorative sheet according to any one of claims 1 to 19 , which is arranged to face the surface light source device. A method for producing a decorative sheet according to any one of claims 1 to 19 ,
producing a first film that will form the pattern layer and a second film that will form the base design layer;
A method for manufacturing a decorative sheet, comprising: removing a portion of the first film and the second film by irradiating a laser beam from the second film side to form an opening. 22. The method for manufacturing a decorative sheet according to claim 21 , wherein the absorption rate of the first film at the wavelength of the laser beam is higher than the absorption rate of the second film at the wavelength of the laser beam. The method for manufacturing a decorative sheet according to claim 21 or 22 , wherein the absorption rate of the first film at the wavelength of the laser beam is 3% or more. The method for producing a decorative sheet according to any one of claims 21 to 23 , wherein the wavelength of the laser light is 900 nm or more and 1300 nm or less.